Apple

Operating System: iOS
Strengths:

• Ecosystem: Seamless integration with other Apple products (Mac, iPad, Apple Watch, etc.).
• Performance: Generally excellent performance due to tight hardware-software integration.
• App Quality: High-quality apps and timely updates.
• Privacy: Strong focus on user privacy and security.
• Resale Value: iPhones tend to retain their value well over time.

Weaknesses:

• Price: Often more expensive compared to other brands.
• Customization: Limited customization options compared to Android.

Samsung

Operating System: Android (with One UI skin)
Strengths:

• Variety: Wide range of devices from budget to premium, including the Galaxy S and Note series.
• Display: Known for high-quality Super AMOLED displays.
• Features: Innovative features such as high refresh rate screens, foldable phones, and S-Pen support.
• Customization: Greater flexibility and customization options with Android.
• Camera: Strong camera performance with advanced features.

Weaknesses:

• Software Updates: Historically slower to roll out Android updates compared to some other brands.
• Bloatware: One UI can come with pre-installed apps that some users may find unnecessary.

Vivo

Operating System: Android (with Funtouch OS or OriginOS)
Strengths:

• Innovative Features: Often introduces unique features like in-display fingerprint sensors and pop-up cameras.
• Camera: Competitive camera performance, particularly in mid-range and high-end models.
• Design: Modern and attractive design with a focus on aesthetics.
• Price-to-Performance: Generally offers good value for money.

Weaknesses:

• Software: Funtouch OS may not be as polished or consistent as stock Android or other custom UIs.
• Brand Recognition: Less global brand recognition compared to Apple and Samsung.

Oppo

Operating System: Android (with ColorOS)
Strengths:

• Design: Sleek and innovative design with attention to detail.
• Charging Technology: Fast charging capabilities, including SuperVOOC technology.
• Camera: Strong camera performance with features like high zoom capabilities and low-light performance.
• Value: Competitive pricing with good value for features offered.

Weaknesses:

• Software: ColorOS can be less intuitive or bloatware-heavy compared to other Android skins.
• Market Position: Less prominent in some regions compared to Samsung and Apple.

Summary

• Apple is known for its premium build, performance, and ecosystem integration but comes with a higher price tag and less customization.
• Samsung offers a broad range of devices with innovative features and strong displays but may have slower software updates and more bloatware.
• Vivo excels in innovative features and design, often providing good value for money, but may have software and brand recognition issues.
• Oppo stands out for its design and fast charging technology, with competitive camera performance, though it might have software quirks.